import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

// Press Shift twice to open the Search Everywhere dialog and type `show whitespaces`,
// then press Enter. You can now see whitespace characters in your code.
public class Main {

        private static final String EMAIL_REGEX = "^[A-Za-z0-9.-]+@[A-Za-z0-9.-]+$";

        public static boolean isValidEmail(String email){
            if(email == null){
                return false;
            }
            Pattern pattern = Pattern.compile(EMAIL_REGEX);
            Matcher matcher = pattern.matcher(email);
            return matcher.matches();
        }
        public static void main (String[] args){
            Scanner scanner = new Scanner(System.in);
            String s = scanner.nextLine();
            if(isValidEmail(s)){
                System.out.println("这是合法的邮箱");
            }else {
                System.out.println("这不是合法的邮箱");
            }


    }
}